Telephone system.



H. P. GLAUSEN. TELEPHONE SYSTEM- APPLIOATION FILED SEPT. s, 11.

1,088,879; Patented Mar. 3, 1914.

WiInE55-E5:

lm EnTUr v AFT-un s tiple jacks.

ran STATES PA 1 carton.

HENRY P. CLAUSEN, OF ROCHESTER, NEW YORK, ASSIGNOR TO STROMBERG-CARLSO N TELEPHONE MANUFACTURING COMPANY, OF ROCHESTER, NEW YORK, A COR- ronA'rIon or NEW YORK.

To all whom it may concern Be it known that I, HENRY P. Cnaosnn, a citizen of the United States, and residentof Rochester, county of Monroe, State of New York, have invented certain new and useful Improvements in Telephone Systems, of which the following is a specification:

My invention relates totelephone systems of the central energy multiple type.

The object of my invention is to provide automatic disconnecting means for the telephone lines whereby subscribers who have been in conversation through a cord circuit may obtain immediate and automatic disconnection from each other by re lacing their receivers upon their switch-1100 s. In this manner the operator is relieved of the necessity of pulling down a 'cord connection immediately upon receiving the disconnect signals,thereby equalizing the operators load and permitting her to take down her cordsduring times when there are no unanswered calls upon the switchboard.

My invention provides for more rapid handling of connections than has been afforded by other manual telephone systems.

Other objects and advantages will be more specifically pointed out in the following description and claims.

My invention is illustrated in the accoxrr panying' drawing in which all apparatus 18;

ceiver 7 adapted to be bridged between the limbs of the line by the contacts of the switch-b00118. Line conductor 4 extends to' the central otfice and thence through con tacts 9 and 10 of cut-oil relay 11, the coil of line relay 12 and conductor 13, to the live pole of battery 14, and line conductor 5 extends to the central otlice and thence through contacts 15'and 16 of cut'ofi' relay 11, to ground. Cut-off relay 11 has normally open contacts 17 and 18 extending, respectively to the ring contacts 19 and the tip contacts 20 of the answering and mul- The sleeve or test contacts 21 of these jacks are connected through the coil of cut-ofi' relay llwith earth. Line relay 12 controls normally open contacts 22 and 23 in the circuit of line lamp 24. The

TELEPHONE SYSTEM.

Serial No. 647,907.

called subscribers line 1 is provided with s mllar apparatus, similarly connected, the like apparatus and conductors of this line being designated by corresponding figures with the suffix The cord circuit for connecting these lines for conversation comprises tip and sleeve voice current conductors, the tip conductor east-ending normally from the tip contact 27 ot the answering plug, through conductor 28, contacts 29 and 30 of relay 31, condenser 32, contacts 33 and 34 of relay 31, conductor 35, and contacts 36 and 37 ofthe operators ringing key 38, to the tip contact 39 of the calling plug. The sleeve voice current conductor extends from the sleeve contact 41 01: the answering plug, through conductor" 42, contacts 43 and 44 of relay 45, condenser 46, contacts 47 and 48 of relay 45, conductor 49 and contacts 50 and 51 of the operators ringing key 38, to the sleeve contact 52 of the calling lug.- This cord circuit is provided with tip and sleeve answer-' nected between the contact 47 of relay 45 and the live pole of battery 14. These four relays are thus connected in bridge of the 'voice current conductors, said bridge in-" cluding the battery 14, whereby transmitter energization is furnished to the voice current conductors through the coils of the relays, and whereby the impedance of these coils prevents the short-circuiting of the voice currents through the central battery. Relay 55 controls normally open contacts and 61, and relay 54 controls normally closed contacts 62 and 63 in the circuit of the answering supervisory lamp 64, this circuit including the coil of relay 31. Therelay 57controls normally open contacts 65 and 66, and the relay 56 controls normally closed contacts 67 and 68 in the circuit of the calling-supervisory 'lamn 69, tl is circuit also including the coil of relay 3 31 has a normally open contact. 70, adapted to connect with the lever 30 upon the actuation of the relay. This contact 70 is cone I Patented Mar. 3, 191

pole of battery 14, and the relay 5 is con- Relay nected through conductor 71 with the live pole of battery 14. Relay 31 also has nor-' through conductor 75 and the coil of relay wit-h ground. The relay 45 has the normally open contact 77, adapted to connect with the lever contact 47 upon the actuation of the relay. This contact 77 is'connected through conductor 78 with the coil of relay 31. Relay 45 also has normally open contacts 79 and 80, contact 80 being connected with the live pole of; battery 14, While-contact 79 is connected with the contact 63 of relay 54. This cord circuit is also provided with .the usual listening key 81, adapted, upon actuation, to place the operators receiver 82, condenser 83, and the secondary 84 of the operators induction coil, in a bridge between the strands of the talking circuit in a manner well known in the art. The operators ringing key 38 has normally open contacts 86 and 87 extending, respectively, to the ringing generator 88 and .through the non-inductive resistance 89, to the live pole of battery 14. I

In the operation of thissystem, the subscriber at sub-station 1 removes his receiver 7 from switch-hock 8, and thus completes a circuit from battery 14, through conductor 13, coil of line relay 12, contacts 10 and 9 of cut-ofl' relay 11, line conductor 4, transmitter 6, receiver 7, contacts ofswitch-hook 8, line conductor 5, and contacts 15 and 16 of cut-ofl relay 11, to ground. The current in this path actuates line relay 12, closing its contacts 22 and 23, thus completing the circuit of the line lamp 24 and displaying that lamp to indicate to the operator that a connection is desired upon the line thus designated. The operator, seeing the display of the line lamp, inserts her answering plug into the jack associated with the lamp and thus completesa circuit from the live pole of'battery 14, through the coil of supervisory relay 55, contacts 44 and 43 of relay 45, conductor 42, sleeve contacts 41 and 21 of the-plug and jack and the coil of cut-off relay 11, to ground. The current in this path actuates relays 11 and 55. The actuation of cut-01f relay llsevers the circuit of the line relay 12, thus efiacing the line lamp 24, and connects the limbs 4 and 5 of the telephone line directly with the ring and tip contacts 19 and 20 of the answering jack. A second circuitis thereby completed from the live pole of battery 14, through the coil of relay 55, contacts 44 and 43-of relay 45, conductor 42, sleeve contact 41 and ring contact 19 of the plug and jack, contacts 17 and 9 of cut-oil relay 11, line conductor 4, transmitter 6, receiver 7, contacts 15 and 18 of cut-0E relay l1, tip contacts 20 and 27 of the jack and plug,-conductor 28, contacts 29 and 30 of relay 31, and the coil of relay 54, to the ground pole of battery 14. The current in this path actuates relays 54 and 55. The actuation of relay 55 closes its contacts 60 and 61 in the circuit of supervisory signal64, but the actuation of relay 54 immediately opens its contacts 62 and 63 in said circuit and prevents the display of the signal 64. The operator now depresses her listening key 81 and obtains the number ofthe desired subscriber. Having done so she inserts her calling plug into the jack of the desired line and depresses her ringing key. A circuit is thus completed. from the live pole of battery 14, through the non-inductive resistance 89', contacts 87 and 51 of the operators ringing key 38, sleeve contacts 52 and 21. or' the plug and jack, and the coil of cut oif relay 11 to ground. The current in this path actuates the cut-oil relay 11 and thus completes a circuit from the ringing generator- 88, through the contacts 86 and 37 of the operators'ringing key 38, tip contacts 39 and 20 of the plug and jack, contacts 18 and 15 of cut-ofi' relay 11 line conductor 5 condenser 2 annunciator3 line condoctor 4?, contacts 9 and 17 of cut-ofi' relay 11 ring and sleeve contacts 19 and 52 of thejack and plug, contacts 51 and 87 of the operators ringing key 38,and the noninductive resistance 89, through the battery 14, to ground, and thus back to the ringing ing generator, being alternating in character, passes the condenser 2 and sounds the annunciator 3 Upon the release of the ringing key 38, the circuit is'completed from generator 88. The current fiom this ringthe live pole of battery 14, through the coil of relay 57, contacts 47 and 48 of relay 45, conductor 49,,contacts 50 and 51 of the 0perators ringing key 38, sleeve contacts 52 and 21 of the plug and jack and the coil of cut-ofi relay 11 to ground. The current in this path maintains the actuation of cutoff relay 11 and actuates the supervisory relay 57. The actuation of relay 5'7 closes its contacts 65 and 66 and thus completes a circuit from the live pole of battery 14,

through contacts 65 and 66 of relay 57, "contacts 67 and 68 of relay supervisory lamp 69 and the coil in relay 31, to ground. The current in this path displays the alling supervisory signal'69, but is not .ufficient to actuate the relay 31, this relay being oi'i'low resistance compared to the resistance of the lamp 69. Upon the response of the called subscriber, a circuit is completed from the live pole of battery 14,

through the coil of supervisory relay 57,

contacts 47 and 48 of relay 45, conductor '49, contacts 50 and 51 or" ringing keyz38,

of switch-hook 8, line conductor 5, contacts 4 sleeve and ring contacts and 19 olt the plug and jack, contacts 17 and 9 ofcut-ofi' relay 11 line conductor 4 transmitter 6,

' its contacts 67 and 68 and thus etlaces the supervisory signal 69. The calling and called subscribers are now connected for conversation, the transmitter energy being 7 fed to the calling subscribers line through the coils of relays 54 and 55, and the transmitter 'energization current being fed to the called subscribers line through coils of relays 56 and 57. The voice currents, being alternating in character and of comparatively high frequency, readily pass through,

the condensers 32 and 46, these condensers simply serving as means for isolating the calling and called subscribers lines so far as the flow of direct currentis concerned.

When the conversation has been terminated and the calling and called subscribers replace their receivers upon their respective switch-hooks, the circuits through relays 54 and 56 are interrupted, permitting the armatures of these relays to return to their normal positions. The closure of contacts 62 and 63 of relay 54 completes the circuit of the answering supervisory si al 64, this circuit including the coil of re ay 31. The closure of contacts 67 and 68 of relay 56 completes the circuit of the calling supervisory signal 69, this circuit also including the coil of relay 31. The current through either supervisory signal 69 or 64 alone is insufiicient to initially actuate relay 31, but the current through these signals in parallel is suflicient for the actuation-of relay 31. That relay is, therefore, actuated at this time, moving all of its contacts to their abnormal positions.

The movement of contacts 30 and 33 of relay31 severs the connection of the tip cord conductors 38 and 35, thus interrupting the circuit of each tip cord strand of the cord circuit and producing the same effect, so far as the subscribers are concerned, as thou h the tips of the plugs were removed from t e jacks with which they are connected.

The closure of contacts 7 2 and 73 of relay 31 completes a circuit from the live pole of battery 14, through conductor 91, the conductor o-rtion of interrupter 74, contacts 72 and 73 of relay. 31, and the coil of relay 45,

,to ground. The current in this path actuates relay 45,moving all of its contacts to their abnormal positions. The movement of the lever contacts 44 and 47 of relay 45 sevlay 31.

ers the sleeve talking strand of the cord circuit, thus entirely disconnecting the calling and called subscribers.

It now becomes necessary to provide means for maintaining the display of supervisory signals 64 and 69 until the operator removes the plug connections from the jacks,

and thereafter to return the apparatus to its normal condition and etlace the supervisory signals 64 and 69. The actuation of relay 57 is now maintained through a circuit which may be traced from the live pole of battery 14, through the coil of relay 57, contacts 47 and 77 of relay 45,conductor 78, and the coil of relay 31, to ground. -This maintains the actuation of relay 57, holds its contacts and 66 in their closed condition, and maintains the circuit of the supervisory signal 69. The circuit of supervisory signal 64 may now be traced from the live pole of battery'14, through contacts 80 and .79 of relay 45, the'signal 64, and the coil of relay 31, to ground. For purposes which will be hereinafter described, the relay 54 is now maintained actuated by current furnished through conductor 71, contacts and 30 of relay 31, and the coil of supervisory relay 54, to ground.

As the interrupter 74 proceeds in its rotation the circuit completed thereby is broken, for example, once in three seconds, the period of interruption being very short, say, .1 of a second. During this interruption the circuit of relay 45 is broken. That relay, therefore, momentarily resumes its normal position. If the calling plug has not already been removed from the jack into which it had been inserted, the circuit through relay 57 will be reestablished through contacts 47 and 48 of relay 45 and the coil of cutoff relay 11 of the line with which the calling plug is connected. Relay 57 will, therefore, remain in its operated condition and the circuit through supervis ory lamp 69 and the coil of relay 31 will notbe interrupted. The current will be interrupted through the lamp 64 at contacts 80 and 7 9 of relay 45, but,'since it' requires less current to maintain the actuation of relay 31 than to initially operate it, relay 31 will remain in its actuated condition. lVhen the calling plug has been removed from the jack, however, and the interrupter 'I-Llias rotated to its open position, the,circuit of relay 45 is interrupted and that relay-resumes its normal position as before, but at this time the circuit of relay 57 is interrupted since there is no path through contacts 47 and 48 and the sleeve of the plug over which current flows to maintain the actuation of relay 57.

position and interrupts the circuit through i the supervisory signal 69 and the coil of re- Relay 31 consequently falls back to its normal position, breaking the circuit bejacks of this line.

tween contacts 72 and 73 of relay 31 so that when the interrupter 74. again closes its circuit the relay 45 will not be again energized. This occurs even while the answering plug is still inserted into the jack of the calling line, the relay 54 being maintained actuated as before described so that, even if the relay 55 is reactuated, due to its circuit beingcompleted through the cut-off relay of the calling line, no current will flow through the supervisory signal 64 and thence through the coil of relay 31, to prevent that relay from falling back to its normal position,

while the relay 45 is in its normal position.

If, during the time that the answering and calllng plugs are still connected with the ]3.Cl S, either or both subscribers with other connections, it is simplynecessary for them to remove their receivers from their hooks in the usual way, whereupon the line lamps of the respective subscribers are displayed in the same manner as was formerlydescribed in-connection with the calling line 1.

It will be understood that the line lamp of the called line 1 may be, and usually is,- located in a difierent switchboard section from that at which the calling plug is connected with a multiple jack of the line, and, therefore, a re-call uponthe called line will be taken care of by-another operator in the usual way without her even knowing that a'plug is connected with one of the multiple However, if are-call occurs upon the calling telephone line, before a plug has been removed from the jack, the line lamp signal will be displayed in proximity with the plug which is inserted in the answering'jack of this line. It is then necessary for the operator to remove the calling plug from the line with which .it

was formerly connected before a second con I nection can be made for this calling tliphone line.

The busy test for this system is made in the usual way, though it will be seen that during the period of interruption at the interrupter 74, which has been assumed to be .1 of one second in every three seconds, a false busy test may be given to the operators. operators to-secure at least three clicks for each busy test. This will insure sufficient lapse of time for the interrupter 74 to have passed over its period of break, so that whenever an operator secures three busy test clicks she will know that a busy test is caused by an actual busy line and not by av line made falsely busy-by the failure of the I operator to remove her plug from its jack after the termination of the conversation. With this system, either a calling or a called subscriber will beable to secure a new connection-in much shorter time than with a system'of the usual multiple type, and, aside from this/the operator will be instructedto This is eliminated by instructing the be applied to other line and cord circuits,

all'such modifications being entirely within the scopeof my invention.

1 claim- 1. In a telephone system, the combination with a pair of telephone lines, of an oper- .ators cord circuit for connecting said lines for conversation, a source of currentassociated with the cord circuit for supplying transmitter current to said lines, a pair of switches in each strand of said cord circuit,

a pair of relays, one controlling the switches of one strand and the other controlling the switches of the other strand, and magnetic means under the control of"the subscribers for closing the circuits of said relays at the termination of a conversation whereby the lines will be automatically disconnected each from the other. I

2. Ina telephonesystem, the combination ,with a pair of telephone lines, of a cord cir cuit for interconnecting said lines, a condenser in each strand of said cord circuit, a pair of normally. closed contacts in each strand of saidcord circuit, one on. web side of said condensers, a pair of relays each controlling a pair of contacts in one strand of said cord circuit; means for operating said relays to sever the strands of the talk-' ing circuit, said means beingiinitially operated when both line circuits are opened at the subscribers stations.

. 3. In a telephone system, the combination with a cord circuit, of ti andsleeve talking strands therefor, relaysor interrupting said talking strands at the termination of a conversation whereby the immediate interruption-of the circuit by the operator isunnecessary, and means to return said relays to their normal condition by the interruption of one of the talking strands when the operator.

finallyremoves the connection.

4. In a telephone system, the combination With a two wire cord circuit, of a pan of supervisory signals therefor, a pair of relays controlling contacts in the talking strands of said cord circuit, said relays being adapted to be actuated upon thedisplay of. both of said supervisory signals to sever the talking strands of the cord circuit,and

means tointerrupt'the circuit of said relays by the removal of the plugs of the cord circuit from their connections. I

5. In a telephonesystem, the combinat on with a cord circuit, of a pair of telephonelines with which said cord-is connected,a

pair of supervisory signals tor the cord circuit, a relay controlling contacts in the sleeve strand of said cord circuit and adapt ed to be actuated to sever said contacts upon the simultaneous display of said supervisory signals, interrupter meansin the circuit of said relay whereby the relay will periodically return to its normal position, a pair of contacts in the circuit of said relay, said contacts being controlled over a circuitiincluding the sleeve strand of said cord circuit and the sleeve of the jack with which said cord is connected during the open, period of said interrupter.

' 6. In a telephone system, the combination with a pair of telephone lines, of a cord circuit for c0! necting said lines for conversation, a pair of relays having contacts adapted to sever the strands of said cord circuit at, the termination of a conversation and before' the cord circuit has been disconnected from said lines, and a circuit periodically com pleted over a strand of said cord circuit for automatically testing the connecting terminal of said cord circuit, and means for intercopi'ea 0! this patent may be obtained for rupting the circults of said relays when such automatic test indicates that the cord circuit has been disconnected from said lines.

7 In a telephone system, the combination with a pair of telephone lines, of a cord circuit for connecting said lines for conversation, means for automatically interrupting the strands of said cord circuit at the termination of a conversation, a circuit periodically completed over the strand of said cord circuit and a jack of one of said linesfor maintaining the actuation of said interrupting means, whereby the strands of the cord circuit will be re-completed when the connection between the cord and a line is finally;-

interrupted.

' Signed by me at Rochester, county of Monroe, and State of New York, in thepresence of two witnesses.

, HENRY P. CLAUSEN.

Witnesses Tnnnsa A. B'UGKLEY,

CLIFFORD C. BRADBURY.

five cents eaohpby addressing the Oommlnioner o! intents,

Washington, 10. e." 

